Aetna Inc. withdrew its request to raise prices for individual policyholders in California by an average of 19% after discovering a flaw in its rate filing with state regulators, according to the California Department of Insurance. California Insurance Commissioner Steve Poizner said Aetna's withdrawal was voluntary. The errors include incorrectly calculating the annual cost of monthly premiums and incorrectly compounding the increases year over year, a spokesman for the department told the Wall Street Journal.